FIELD: digital processing of voice signals, which are transmitted through communication lines. SUBSTANCE: method involves detection of adjacent high-level doubled (having opposite signs) leaps in level of first derivative of voice signal by means of storing previous piece of voice signal, measuring mean absolute value of first signal derivative during this piece by means of accumulation of absolute values of difference between two adjacent PCM signal samples and setting two identical adaptive opposite-sign thresholds which are proportional to mean absolute value of first derivative. If two adjacent PCM signal samples exceed thresholds, anomalous digital error is detected and corrected by means of alternating inversion of high-order bits of PCM code, until doubled leaps of first derivative are removed. EFFECT: decreased requirements for noise protection of communication lines, decreased cable cost, or increased length of retransmission lines, or increased relative number of pairs to be compressed in cables, while keeping constant subjective perception quality of voice. 4 dwg
